State-owned electricity company PT PLN began to cut its power supply from the Java-Bali power grid system Tuesday after appealing to household and industrial consumers to limit usage during peak hours.

The drop in supply is due to malfunctions in several power plants that are expected to take at least two weeks to repair.

"At 8 a.m., we had to cut our electricity supply by 240 megawatts (MW) and at 2 p.m. by 250 MW," Mulyo Adji, PLN general manager of electricity supply and control for Java and Bali, said Tuesday.

He added that two gas-fired plants in Muara Karang with a capacity of 500 MW and in Tanjung Priok with a capacity of 1,050 MW, both in North Jakarta, were forced to reduce capacity due to a lowered gas supply from a rupture in BP West Java's gas pipeline, which officials estimate may take more than two weeks to repair.

The coal-fired Paiton Unit Five, with a capacity of 600 MW, also suffered from a malfunction of its coal plant, which supplies the plant with powdered coal.

The problems have led to a power deficit in the Java-Bali system of as much as 480 MW, Mulyo said.

The other three coal-fired plants -- Suralaya Unit Six with a capacity of 600 MW, Paiton Unit Two with a capacity of 400 MW and Paiton Unit Eight with capacity of 600 MW -- are currently undergoing maintenance procedures.

Mulyo, warning the shortage could worsen, said that it was important for households and industrial users to participate in energy saving measures, particularly by reducing usage during peak hours to avoid blackouts.

He said that PLN did not adopt the rotation power cut on Monday evening because customers apparently followed the appeal to reduce their usage during peak hours. The company also reactivated a 600 MW gas-fired plant which recently underwent maintenance work.

"Usually at night the peak demand reaches 14,180 MW. But due to the public's reduction of consumption, demand dropped to 13,858 MW. So, last night there was no power blackout."

As surging electricity demand outstrips supply, the country, particularly areas of Sumatra, Java and Bali, has experienced an increasing number of power blackouts during the last few years.

Indonesian Employers Association (Apindo) chairman Sofjan Wanandi said the utility company should not alarm the public and industries by requesting they cut their electricity usage.

"We cannot operate our business without having power certainty from the PLN. If that happened, we could not realize all the orders on time. That means we could be penalized," Sofjan was quoted by detik.com news portal as saying Tuesday.

He said industries particularly vulnerable to power cuts were textile producers, iron and steelmakers as well as petrochemical and synthetic fiber plants.

"That could reduce production. But we cannot calculate how much reduction it could cause," he said. "The rotational power cut will certainly have a multiplier effect."